EP2438851A2 - Microcontrolled electrocardiographic monitoring circuit with differential voltage encoding - Google Patents

Microcontrolled electrocardiographic monitoring circuit with differential voltage encoding Download PDF

Info

Publication number
EP2438851A2
EP2438851A2 EP11184341A EP11184341A EP2438851A2 EP 2438851 A2 EP2438851 A2 EP 2438851A2 EP 11184341 A EP11184341 A EP 11184341A EP 11184341 A EP11184341 A EP 11184341A EP 2438851 A2 EP2438851 A2 EP 2438851A2
Authority
EP
European Patent Office
Prior art keywords
voltage
circuit
feedback
value
values
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP11184341A
Other languages
German (de)
French (fr)
Other versions
EP2438851A3 (en
Inventor
Jason Felix
Gust H. Bardy
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Cardiac Science Corp
Original Assignee
Cardiac Science Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to US12/901,460 priority Critical patent/US8239012B2/en
Application filed by Cardiac Science Corp filed Critical Cardiac Science Corp
Publication of EP2438851A2 publication Critical patent/EP2438851A2/en
Publication of EP2438851A3 publication Critical patent/EP2438851A3/en
Application status is Withdrawn legal-status Critical

Links

Images

Classifications

    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/04Measuring bioelectric signals of the body or parts thereof
    • A61B5/0402Electrocardiography, i.e. ECG
    • A61B5/044Displays specially adapted therefor
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/04Measuring bioelectric signals of the body or parts thereof
    • A61B5/0402Electrocardiography, i.e. ECG
    • A61B5/0404Hand-held devices
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/04Measuring bioelectric signals of the body or parts thereof
    • A61B5/0402Electrocardiography, i.e. ECG
    • A61B5/0428Input circuits specially adapted therefor
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/04Measuring bioelectric signals of the body or parts thereof
    • A61B5/0402Electrocardiography, i.e. ECG
    • A61B5/0432Recording apparatus specially adapted therefor
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/72Signal processing specially adapted for physiological signals or for diagnostic purposes
    • A61B5/7203Signal processing specially adapted for physiological signals or for diagnostic purposes for noise prevention, reduction or removal
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/04Measuring bioelectric signals of the body or parts thereof
    • A61B5/04012Analysis of electro-cardiograms, electro-encephalograms, electro-myograms
    • A61B5/04017Analysis of electro-cardiograms, electro-encephalograms, electro-myograms by using digital filtering
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61BDIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00Detecting, measuring or recording for diagnostic purposes; Identification of persons
    • A61B5/72Signal processing specially adapted for physiological signals or for diagnostic purposes
    • A61B5/7232Signal processing specially adapted for physiological signals or for diagnostic purposes involving compression of the physiological signal, e.g. to extend the signal recording period

Abstract

A microcontrolled electrocardiographic monitoring circuit (10) with differential voltage encoding is provided. An input signal path (23) includes an electrode (12a), a low pass filter (13a), and an amplifier (13b), which are each connected in-line. The electrode (12a) senses an input signal via a conductive surface and the amplifier (13b) outputs a filtered amplified output signal. A microcontroller circuit (11) includes an input codec, an analog-to-digital converter (14), and an encoder (33). The analog-to-digital converter (14) is connected to the input signal path (23) through an output of the amplifier (13b) and converts the filtered amplified output signal into a data stream (31) of discrete digital values. The encoder (33) determines a differential voltage between a current discrete digital value and a prior discrete digital value in the data stream (31). Persistent memory (17) is connected to the microcontroller circuit (11) via a peripheral serial interface bus (18), wherein the differential voltages for each of the discrete digital values in the data stream (31) are stored into the persistent memory (17).

Description

    Field
  • This application relates in general to electrocardiography and, in particular, to a microcontrolled electrocardiographic monitoring circuit with differential voltage encoding.
  • Background
  • The heart circulates blood throughout the body in a continual cycle of electrical stimulation of cardiac muscle cells. At rest, each muscle cell accumulates an electrical charge across its cell membrane that is then depolarized during each heart beat. Initially, the cells of the sinoatrial node in the right atrium spontaneously depolarize and create a cardiac action potential of electrical impulses that rapidly propagates outward. The cardiac action potential stimulates muscle cells of the atrial myocardium to depolarize and contract in unison in systolic contraction, after which the cardiac action potential encounters the atrioventricular node located at the juncture of the atria and ventricles near the center of the heart. The atrioventricular node slightly delays cardiac action potential propagation to ensure complete drainage of blood from the atria after which the muscle cells of the ventricular myocardium are stimulated into systolic contraction and thereby complete the heart beat cycle.
  • The depolarization of the muscle cells of the atrial and ventricular myocardium act as sequential voltage sources, which generate a current flow across the thoracic region of the body and result in a characteristic signal on the body surface. In a typical ECG monitor, cardiac action potentials occur between 0.05 Hz to 150Hz with a signal strength of around 3mVp-p (peak-to-peak). Although miniscule, the current flow can be measured to characterize the electrical activity of the heart using an electrocardiographic (ECG) monitor or similar device. Voltage differentials from pairings of the electrodes are filtered, amplified, and combined into P, QRS, and T complexes.
  • Conventionally, cardiac action potentials are detected through electrodes attached to the skin on the chest and limbs based on the American Heart Association's classic 12-lead placement model, such as P. Libby et al., "Braunwald's Heart Disease - A Textbook of Cardiovascular Medicine," Chs. 11 and 12 (8th ed. 2008), the disclosure of which is incorporated by reference. Both traditional in-clinic and ambulatory Holter-style ECG monitors follow the standard 12-lead model with variations on numbers and placement of leads. Generally, limb lead electrodes are placed on each arm and on the left leg, while precordial lead electrodes are placed on the left upper chest region over the heart. The limb leads can be re-positioned as necessary to compensate for variability in patient anatomy due to tissue and bone density and heart position.
  • Accurate ECG recording requires the absence of significant ambient noise. The 12-lead model attempts to maximize cardiac action potential signal strength. However, ECG monitors are still affected by environmental noise and feedback. The body acts as an antenna that is susceptible to electromagnetic (EMF) noise, which is often caused by power lines. Cardiac action potentials are inherently weak signals easily overwhelmed by such ambient interference. Skin-to-electrode impedance is around 51 kOhms. 50 Hz or 60 Hz power line EMF interference, depending on country, is filtered from the input signal using a filter, while baseline low-frequency wander is normally corrected by using a feedback system.
  • Conventional monitoring circuits combine physical shielding, analog filtering, and digital filtering to reduce noise. However, noise filtering methods can cut dynamic range, particularly low frequency sensitivity to keep signals within a permissible dynamic range. As a consequence, ECG quality and clinical value can suffer when extremely low frequency content is lost. There are a variety of analog feedback circuits in conventional ECG monitors to drive a common mode voltage and keep the amplifiers from oversaturation. For instance, in a right leg drive (RLD) circuit, a network of resistors sense common mode voltage on a body, which is then inverted, amplified, and fed back into the body through a reference electrode. Consequently, the body becomes a summing junction in a feedback loop. Negative feedback thereafter drives common mode voltage to a nominal value.
  • Although effective at countering respiration, wander and drift, such conventional analog RLD circuits increase circuit complexity and cost and destroy very low frequency content. Even though RLD circuits typically drive less than one microampere of current into the right leg, at a minimum, a resistor feedback network and an output op-amp that drives a reference electrode must be powered and placed in the circuit. The constant power draw to drive the circuit can tax power budget constraints, particularly where the circuit is in an ambulatory battery-powered ECG monitor.
  • For instance, U.S. Patent No. 5,392,784, issued February 28, 1995 to Gudaitis , discloses a virtual right leg drive circuit for common mode voltage reduction. A circuit senses common mode voltage received by inputs from a signal amplifier and generates a compensation voltage, representative of the common mode voltage. A capacitance to chassis ground receives a voltage representative of the compensation voltage. The circuit and the capacitance cause the amplifier power supply voltages to track the common mode voltage. The capacitance permits the feedback loop gain to be increased to reduce common mode voltage errors, but at the cost of increased circuit complexity.
  • U.S. Patent application, Publication No. 2007/0255153, filed November 1, 2007, to Kumar et al. ; U.S. Patent application, Publication No. 2007/0225611, filed February 6, 2007, to Kumar et al. ; and U.S. Patent application, Publication No. 2007/0249946, filed February 6, 2007, to Kumar et al. disclose a non-invasive cardiac monitor and methods of using continuously recorded cardiac data. A heart monitor suitable for use in primary care includes a self-contained and sealed housing. Continuously recorded cardiac monitoring is provided through a sequence of simple detect-store-offload operations. An action sequencer state machine directs the flow of information to either memory or to a switched I/O unit without feedback control. In one embodiment, a 24-bit analog-to-digital converter converts continuously detected ECG information into uncompressed 8-bit data. Amplification circuitry is not required, as amplification and scaling are replaced by selecting an 8-bit data resolution out of a possible 24-bit range. Additionally, the 24-bit to 8-bit selector serves as a scaler to keep signal excursions within the numeric range of the analog-to-digital converter and to provide image scaling to the end user. The stored ECG data can be retrieved and analyzed offline to identify ECG events.
  • U.S. Patent application, Publication No. 2008/0284599, filed April 28, 2006, to Zdeblick et al. and U.S. Patent application, Publication No. 2008/0306359, filed December 11, 2008, to Zdeblick et al. , disclose a pharma-informatics system for detecting the actual physical delivery of a pharmaceutical agent into a body. An integrated circuit is surrounded by pharmacologically active or inert materials to form a pill, which dissolve in the stomach through a combination of mechanical action and stomach fluids. As the pill dissolves, areas of the integrated circuit become exposed and power is supplied to the circuit, which begins to operate and transmit a signal that may indicate the type, A signal detection receiver can be positioned as an external device worn outside the body with one or more electrodes attached to the skin at different locations. The receiver can include the capability to provide both pharmaceutical ingestion reporting and psychological sensing in a form that can be transmitted to a remote location, such as a clinician or central monitoring agency.
  • Therefore, a need remains for an approach to efficiently negate the affects of environmental interference, while preserving dynamic signal range in an ECG monitor and simultaneously reducing the complexity of ECG circuitry, especially for designs intended for low-cost and disposable ECG monitoring technologies.
  • Summary
  • A monitoring circuit for ECG recording operates under microprogrammed control on a single channel of analog input signals. The signals originate as cardiac action potentials sensed from the skin's surface by a single sensing electrode pair, although multiple sensing electrode pairs could be employed with modifications to the monitoring circuit to factor in multiple input signal channels. The monitoring circuit provides digitally-controlled feedback in lieu of employing a conventional right leg drive or similar feedback circuit. The analog input signals are converted into digitized form and encoded for efficient compressed data storage in non-volatile memory. Feedback markers are stored with the digitized data. Following monitoring, the discrete digital values can be retrieved from the non-volatile memory and the original analog signal can be reproduced. The digitization and compression of the original analog signal requires less memory to store long term ECG data while providing improved signal reproduction accuracy. The accuracy of the reproduced analog signal can be improved by correcting the decoded data for power supply depletion. As well, the resolution of the signal can be increased by removing any feedback that was introduced by the microcontroller during monitoring.
  • One embodiment provides a microcontrolled electrocardiographic monitoring circuit with differential voltage encoding. An input signal path includes an electrode, a low pass filter, and an amplifier, which are each connected in-line. The electrode senses an input signal via a conductive surface and the amplifier outputs a filtered amplified output signal. A microcontroller circuit includes an input codec and further includes an analog-to-digital converter and an encoder. The analog-to-digital converter is connected to the input signal path through an output of the amplifier and converts the filtered amplified output signal into a data stream of discrete digital values. The encoder determines a differential voltage between a current discrete digital value and a prior discrete digital value in the data stream. Persistent memory is connected to the microcontroller circuit via a peripheral serial interface bus, wherein the differential voltages for each of the discrete digital values in the data stream are stored into the persistent memory.
  • A further embodiment provides a microcontrolled electrocardiographic monitoring circuit with discrete data encoding. An input signal path includes an electrode, a low pass filter, and an amplifier, which are each connected in-line. The electrode senses an input signal via a conductive surface and the amplifier outputs a filtered amplified output signal. The microcontroller firmware includes an input codec and driven by hardware that includes an analog-to-digital converter and an encoder. The analog-to-digital converter is connected to the input signal path through an output of the amplifier and converts the filtered amplified output signal into a data stream of discrete digital values. The encoder determines a differential voltage between a current discrete digital value and a prior discrete digital value in the data stream and selects an encoded value representative of the differential voltage. Persistent memory is connected to the microcontroller circuit via a peripheral serial interface bus, wherein the encoded values for each of the differential voltages are stored into the persistent memory.
  • A still further embodiment provides a computer-implemented electrocardiographic data processor. A download station physically interfaces to an electrocardiographic monitoring circuit that includes a microcontrolled electrocardiographic monitoring circuit and a memory. The download station retrieves digitally-encoded data values representative of analog cardiac action potential signals from the memory of the monitoring circuit. A post-processing application includes an output codec and executes on a computer that is connected to the download station. The post-processing application further includes a set of enumerated output voltages and ranges of voltage differences and a decoder. The set of enumerated output voltages and ranges of voltage differences that each correspond to lower and upper bounds of voltage is defined. The decoder identifies the enumerated range within which each retrieved data value falls by comparing the retrieved data value to the lower and upper bounds of voltage. The decoder also reproduces the analog cardiac action potential signals by selecting the output voltages corresponding to the identified enumerated ranges as the analog cardiac action potential signals.
  • The microcontrolled ECG monitoring circuit offers a lower power design, has a lower component and power cost, and provides flexible control over input signal processing, as well as providing better post-processing options with extended dynamic range. The circuit is particularly suited to ambulatory ECG monitoring from a midline sternum-centered position, which provides a superior body position for home application and for patient comfort when used for long-term monitoring, despite the need for stronger cardiac action potential signal amplification to compensate for a short signal vector characteristic of this sternal location. In contrast, conventional ECG monitoring circuits would saturate at comparably high signal amplification levels and rely on modifying lead placement to compensate for patient physical variability.
  • Further, the microcontrolled ECG monitoring circuit enables an ambulatory ECG monitor to be built at low cost, size and weight. For instance, a disposable ECG monitor in the form of an adhesive patch can be constructed with a weight of less than one ounce and inter-electrode spacing of less than 6cm, which presents three advantages. First, costs for shipping the monitors to clinics, hospitals, pharmacies, and other locations are reduced, especially when large quantities must be mailed around the world. Second, small size and weight ambulatory ECG monitors can be easily carried in the pockets of health care providers and therefore applied upon demand without the need to either retrieve the monitors from a special location or to send the patient to a separate laboratory. Third, small, lightweight ambulatory ECG monitors reduce shear forces on the skin, which further ensures good signal acquisition and long-term ECG recording by facilitating adherence to the skin and comfort for the patient.
  • Still other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein is described embodiments of the invention by way of illustrating the best mode contemplated for carrying out the invention. As will be realized, the invention is capable of other and different embodiments and its several details are capable of modifications in various obvious respects, all without departing from the spirit and the scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive.
  • Brief Description of the Drawings
    • FIGURE 1 is a schematic diagram showing a microcontrolled electrocardiographic monitoring circuit with differential voltage encoding in accordance with one embodiment.
    • FIGURE 2 is a functional block diagram showing an input codec for the monitoring circuit of FIGURE 1.
    • FIGURE 3 is a block diagram showing, by way of example, a header schema used by the monitoring circuit of FIGURE 1.
    • FIGURE 4 is a functional block diagram showing an output codec for the monitoring circuit of FIGURE 1.
    Detailed Description
  • Low pass and high pass filters attenuate input signals to remove noise and other undesirable components of an electrocardiographic signal. Physical shielding increases weight and affects the selection of housing materials. Further, traditional feedback circuits, such as right leg drive (RLD) circuits, introduce added circuit complexity, raise component cost, and require increased power to drive inverted common mode voltage into the body as negative feedback. Conventional approaches are unsatisfactory when used in an ECG monitor for extended operation, particularly in ambulatory ECG monitoring that can potentially capture and record a large body of physiological data, while being reliant on a self-contained and finite power source.
  • Moreover, conventional forms of ECG monitoring, including ambulatory ECG monitoring, rely on the standard 12-lead placement model, which places the precordial lead electrodes over the left upper chest in close proximity to the heart and at a location of strongest ventricular cardiac action potential signal strength. In turn, the monitoring circuitry relies on the superior signal strength from over-the-heart electrode placement and the relatively long signal vector length that is afforded by lead placement over a wider physical expanse of the body. For instance, signal amplification assumes a signal strength of around 3mVp-p (peak-to-peak).
  • The 12-lead placement model, however, is poorly suited to long term ambulatory monitoring. In addition, recording of the atrial cardiac action potential (or P-Wave) can be inadequate thereby interfering with arrhythmia diagnosis. Moreover, in-clinic ECG monitoring assumes the patient will remain relatively stationary and limb leads can be repositioned as necessary to compensate for variability in patient anatomy. In contrast, during ambulatory monitoring, a patient's body is in continual motion, even during sleep, albeit to a lesser degree. Electrodes are apt to detach and the quality of signal acquisition depends on the degree to which each electrode maintains its original position..
  • Ambulatory ECG monitoring can be improved by locating the lead electrodes to body positions better adapted to minimize artifacts due to body movement. Although rarely used, no position is better suited for ease of application and P-wave signal acquisition during ambulatory ECG monitoring than the patient's chest at midline, covering the center third of the sternum and centered mid-sternum between the manubrium and the xiphoid process. This location provides a superior location for long term ambulatory monitoring, such as described in commonly-assigned U.S. Patent application, entitled "Ambulatory Electrocardiographic Monitor and Method of Use," Serial No. 12/901,444, filed October 8, 2010 , pending, the disclosure of which is incorporated by reference. A pair of electrodes, spaced less than 6cm apart, are placed midline in a narrow patch electrode designed to conform to the sternal surface, which is non-planar, even in men. In one embodiment, the electrodes 48 have an approximately 2.5 cm spacing. The midline sternum-centered monitoring site enables both good amplitude P-wave and QRS-wave acquisition. However, the electrode placement results in a short signal vector that diminishes signal strength to about 25% of the signal amplitude obtainable from more widely spaced electrodes as used in traditional ECG monitoring technologies.
  • Digitally-controlled ECG monitoring circuits provide the ability to handle the wide dynamic range occasioned by the short signal vector and low signal strength afforded by a midline sternum-centered ambulatory monitoring location. FIGURE 1 is a schematic diagram showing a microcontrolled ECG monitoring circuit 10 with differential voltage encoding in accordance with one embodiment. The monitoring circuit 10 can be used in all forms of ECG monitoring, including traditional in-clinic ECG monitoring, but is particularly suited to self-powered ambulatory ECG monitoring for use over an extended period of one to 30 days or longer. For clarity, only the principal components of the monitoring circuit 10 proper will be discussed. Ancillary components, such as power supply, external device interface, and support circuitry, will be skipped.
  • The components of the monitoring circuit 10 are specifically selected to reduce overall cost. In one embodiment, the monitoring circuit 10 operates on a single channel of analog input signals. The signals originate as cardiac action potentials sensed on the skin's surface by two electrodes 12a, 12b, although multiple sensing electrodes could be employed with modifications to the monitoring circuit to factor in multiple input signal channels. The analog components define two low capacitance signal paths 23, 24 for respectively providing the analog input signal and driving a microcontroller-determined output signal into the body. The input signal path 23 includes an input electrode 12a connected in-line to a low pass filter (LPF) 13a and an amplifier 13b. The input electrode 12a has a conductive surface, such as silver-silver chloride, for sensing cardiac action potentials on the skin's surface. The output signal path 24 includes an output electrode 12b connected inline to a buffer circuit 20 and a pair of drive resistors 21a, 21b that are connected in parallel. The output electrode 12b similarly has a conductive surface, such as silver-silver chloride, and drives a feedback signal to cancel out very low frequency bias, which could be caused by ECG electrode mismatch or other causes.
  • The digital components include a microcontroller 11 and persistent non-volatile memory 17, such as electrically-erasable programmable read-only memory (EEPROM) or "flash" memory. The microcontroller 11 includes components conventionally found in micro control processors, including accumulators, comparators, and related logic components. In one embodiment, the microcontroller is an R8C/M12 microcontroller, manufactured by Renesas Electronics Corporation, Tokyo, Japan. The monitoring circuit 10 operates under the control of the microcontroller 11 that executes an instruction set (not shown) persistently stored as firmware in the non-volatile memory 17. Alternatively, the instruction set can be stored in a programmable logic array (PLA), volatile random access memory (RAM), or other forms of microcontroller-readable storage structure. The instruction set defines the type of feedback and form of encoding employed by the microcontroller 11. The instruction set can be changed to meet different accuracy requirements. Accuracy generally entails a tradeoff between input frequency bandwidth and sampling. In turn, changes to those factors affect the encoding or compression ratio, CPU utilization, and power budget.
  • The microcontroller 11 is interfaced to the input signal path 23 through an on board analog-to-digital controller 14 (ADC) connected to the output of the low pass filter 13a and the amplifier 13b, which receive a reference signal 22 from the output of buffer circuit 20. The analog signals are of low amplitude. Due to the sternum-centered location of the input electrode 12b, the amplifier 13b must boost an analog input signal of around 0.5-3mVp-p with a signal-to-noise ratio (SNR) of about 80dB. The exceptional SNR found in the sternal location improves waveform quality and partially compensates for the short signal vector resulting from close electrode placement. In contrast, the noise floor encountered by a conventional ECG monitoring circuit is typically much higher and comparable amplification would result in a poor signal with low amplitude, rather than a usable data signal.
  • A conventional RLD circuit applies negative feedback into the patient's body to drive common mode voltage to a nominal value, but at the expense of additional circuit complexity, cost, and weight. In contrast, the monitoring circuit 10 uses the reference signal 22 to inject a feedback signal into both the ADC 14, the amplifier and the patient's body. Thus, circuit noise is injected into the input signals, rather than being filtered. The monitoring circuit 10 is thereby able to operate without physical shielding, with minimal analog filtering, no digital filtering, and with minimal power filtering components, when used in an ambulatory ECG monitor. Physical noise shielding is eliminated through unique printed circuit board design and layout, as well as careful selection of electronic components that naturally dampen unwanted signals.
  • The ADC 14 converts the analog input signal into a discrete digital value. In one embodiment, the discrete digital values are generated by the ADC 14 with a 12-bit resolution at a 176Hz sampling rate, although other sample sizes and sampling rates are often utilized. The microcontroller 11 is interfaced to the output signal path 24 through an input/output module 19 (I/O). The I/O module 19 converts a digital feedback signal, as further described below with reference to FIGURE 2, The microcontroller 11 is interfaced to the non-volatile memory 17 through serial peripheral interface bus module (SPI) 18 that synchronously reads and writes data frames of digital values to and from the non-volatile memory 17. The microcontroller 11 could also be interfaced to other analog and digital components and to monitor other physiological signals.
  • The firmware-stored instruction set functionally defines an input coder/decoder (codec) 16 that manages onboard processing of the digitally-converted analog input signal for sensed cardiac action potentials. FIGURE 2 is a functional block diagram showing an input codec 16 for the monitoring circuit 10 of FIGURE 1. In one embodiment, the input codec 16 is optimized to ignore clinically insignificant variations in the data to achieve improved compression ratios through data encoding. The digitization and compression of the original analog signal requires less memory to store long term ECG data while providing improved signal reproduction accuracy. Alternatively, clinically insignificant variations could be processed, but at the cost of increased processing complexity, lowered storage capacity, and faster power depletion.
  • The input codec 16 functionally defines a feedback generation module 32 and encoder 33. The feedback generation module 32 receives a data stream 31 of discrete digital values from the ADC 14. In one embodiment, the feedback generation module 32 selectively samples every fourth value, although other feedback sampling frequencies could be utilized, including sampling of every digital value received.
  • When the input signal approaches a bias threshold of ±10% of the maximum level of the system, the mode number is adjusted. For example, if the input signal reaches +10% of the maximum value, the mode number is incremented by one and the feedback is adjusted accordingly. Feedback levels are defined for an enumerated set of feedback modes, as shown, by way of example, in Table 1. Each feedback mode (Column 1) specifies bias controls for a pair of drive resistors 21a, 21b and corresponds to a range of lower and upper bound threshold tolerances, here, shown as percentages of maximum amplitude saturation level for the amplifier 13b (Column 3). The bias controls determine the value of the feedback signal (Column 2) that is used to adjust the pair of drive resistors 21a, 21b during monitoring. Table 1.
    Mode Values of Drive Resistors Mode Number
    Fast High Both Resistors Drive High 2
    High One Resistor Drives High 1
    Off One Resistor Drives Low, One Resistor Drives High 0
    Low One Resistor Drives Low -1
    Fast Low Both Resistors Drive Low -2
    Other ranges of threshold tolerances could be utilized, such as subthresholds representing values for the input digital value that are less than the bias saturation threshold. Furthermore, instead of constant outputs to the drive resistors, a pulse width modulated signal could be provided to increase dynamic range.
  • The input value is compared to each of the ranges of bias saturation thresholds by the feedback generation module 32. Feedback is activated when the input signal gets too close to the saturation point of the input amplifier 13b, such as described in commonly-assigned U.S. Patent application, entitled "Microcontrolled Electrocardiographic Monitoring Circuit with Feedback Control," Serial No. 12/901,449, filed October 8, 2010 , pending, the disclosure of which is incorporated by reference. For instance, an input digital value reflecting a signal strength of up to 10% of the maximum amplitude saturation level results in a feedback signal that increases the amount of positive feedback that changes the drive settings of the drive resistor 21a, 21b. The range of threshold closest to, but not exceeding, the input value is generally selected, although other selection criteria could alternatively be used. The feedback signal is expressed as a pair of settings for the drive resistors 21a, 21b, which are output through feedback hardware 35 that includes the input/output module 19 and circuitry to convert the two drive resistor settings into analog signals. The outputs of the drive resistors 21a, 21b feed into the buffer circuit 20 and are driven into the body through the output electrode 12b as feedback.
  • To enable resolution extension during post-processing, the feedback generation module 32 also injects a feedback marker in sequence into the data stream 31 to indicate the change in feedback mode. In one embodiment, the feedback marker is included in a three-nibble header, further described below with reference to FIGURE 3, although other types of data markers could be utilized. In a further embodiment, the feedback generation module 32 employs hysteresis to help prevent too frequent changes in feedback mode.
  • The encoder 33 employs discrete variable slope encoding to store the digitally-converted analog input signals for sensed cardiac action potentials in an encoded or compressed form. The encoder 33 receives the data stream 31 from the feedback generation module 32. The encoder 33 then determines the difference in voltage between the current digital value and the prior value output by the input codec 16 to data storage 34 that includes the non-volatile storage 17.
  • Encoding the voltage differentials between successive digitized input signals provides more efficient data storage than storing each discrete voltage, while still retaining the ability to reproduce the original analog input signal during post-monitoring data analysis. A file system is not required and variable slope encoding provides a 3:1 compression ratio for 12-bit input, in contrast to the more typical 1.5:1 compression ratio used in conventional ambulatory ECG monitors utilizing traditional run-length-based encoding. Voltage differential encoding is also memory and process efficient. In one embodiment, the voltage differences are stored as nibbles that represent four-bit signed integers, where a most-significant-bit set to high indicates a negative value. To retain whole byte alignment in memory, the nibbles are first accumulated into single-byte or multi-byte values before being written out to the data storage 34, although other sizes of data storage elements, such as half-word, word, and block sizes, and deferred or immediate data write-out schemes could be utilized.
  • The differences in voltages may be positive or negative. Each voltage difference is encoded by use of an encoding table, as shown, by way of example, in Table 2. The voltage difference must fall within an enumerated range of input values (Column 1) and is encoded (Column 3). The output values (Column 2) corresponding to each enumerated range are used to reproduce the original input signal. If the input and output values cannot be matched, the difference between the values is recorded and is used to calculate the next output value. Table 2.
    Input Value Output Value Encoded Value
    ≥32 32 7
    31 to 24 24 6
    23 to 16 16 5
    15 to 8 8 4
    7 to 4 4 3
    2 to 3 2 2
    1 1 1
    0 0 0
    -1 -1 -1
    -2 to -3 -2 -2
    -7 to -4 -4 -3
    -15 to -8 -8 -4
    -23 to -16 -16 -5
    -31 to -24 -24 -6
    <-32 -32 -7
    Header Header -0
    The enumerated ranges for the input values in the encoding table can also be changed to support increased accuracy at the cost of decreased high frequency response performance, or vice versa.
  • Voltage differences between sensed activation potential voltages are recorded as discrete digital values in a continuous data stream stored in non-volatile memory. Additionally, events are recorded in headers inserted into the data stream for use during post-processing. FIGURE 3 is a block diagram showing, by way of example, a header schema used by the monitoring circuit 10 of FIGURE 1. In one embodiment, each header is three nibbles long, with the first nibble containing a header indicator. Headers are marked with negative zero values, although other marker values could be used. The body of the header indicates three types of events: resets, button presses, and changes in feedback, described supra. A reset can occur when the monitoring circuit 11 encounters a predefined condition, generally representing an error or alarm that requires the circuit to be reset. A reset is marked in the data stream by setting the output value to the value of the nibble that precedes the header. A button press records the physical pressing of a switch or button on the ECG monitor itself, where supported by the hardware. Finally, feedback marker is stored as the last nibble in the header. Other header schemas and content could be utilized.
  • Data decoding is performed offline, which physically interfaces to the monitoring circuit 10 and retrieves the recorded data stream from the non-volatile memory 17 through a download station. The retrieved data stream is then processed by a computer workstation that executes a post-processing application that implements an output codec to reproduce the original cardiac action potential signal. FIGURE 4 is a functional block diagram showing an output codec 41 for the monitoring circuit 10 of FIGURE 1. The computer workstation can either be a purpose-built device or personal computer executing application programs. The output codec 41 is implemented in firmware or software as a set of instructions for execution by the computer workstation.
  • The output codec 41 functionally defines a decoder 43, reference compensation module 44, and feedback cancellation module 45. The decoder 43 retrieves stored voltage differences from data storage 42, which generally will be the non-volatile memory 17 of the monitoring circuit 11 if the data has not yet been physically retrieved from the ECG monitor. In one embodiment, the voltage differences of the cardiac action potentials are encoded as nibbles that represent four-bit signed integers with headers encoded using three contiguous nibbles.
  • The decoder 43 processes the data retrieved from the data storage 42 on a nibble-by-nibble basis. Each nibble represents a voltage difference over the last observed voltage. Each retrieved data value is decoded into its corresponding output value, as shown, by way of example, in Table 2. In one embodiment, the decoded values are 12-bit digital values, which reflects the original 12-bit resolution used during sampling, although other sizes could be utilized. The decoded values can be extended to much higher resolutions through feedback cancellation, as further described infra.
  • The first nibble of every header contains a negative zero nibble. Thus, upon encountering a negative zero nibble, the next byte of data is processed by the decoder 43 to identify the event represented, that is, a reset, a button press, feedback, or a combination thereof. Thereafter, the event is processed by the download station, or offline, as appropriate. For instance, a button press event may cause the download station to place a visual indication and time stamp in the QRS complex that is ultimately reproduced from the recorded set of voltage differences. In turn, the time stamp can be correlated with subjective impressions recorded by the patient in a personal diary during the period of monitoring, such as described in commonly-assigned U.S. Patent application, entitled "Computer-Implemented System And Method For Evaluating Ambulatory Electrocardiographic Monitoring of Cardiac Rhythm Disorders," Serial No. 12/901,461, filed October 8, 2010 , pending, the disclosure of which is incorporated by reference. Similarly, a reset event may signal a programmatic error that requires debugging, a hardware concern, including component fault, software failure, or other considerations underlying monitoring circuit reset.
  • The sensitivity of the monitoring circuit 10 increases over time as its finite power supply is depleted. Thus, following decoding, the reference compensation module 44 receives the retrieved data, which is then normalized to counteract the affect of power supply depletion over the monitoring period. The decoded values are scaled based on the discharge profile 47 of the ECG monitor's power supply, typically a battery or similar finite power cell. The analog components of the monitoring circuit 10 are referenced to the power supply. During runtime, battery voltage quickly decreases and then stays constant for most of the discharge profile, then quickly ramps down again. To maintain accuracy, the voltages represented by each of the discrete digital values decoded by the decoder 43 must be adjusted to account for battery discharge. Writing data to non-volatile memory requires the most power. The number of write operations into the non-volatile memory can be determined based on the total number of samples. The amount of voltage correction required can be determined based on the placement of a particular sample within the ordering of the total body of samples recorded. For instance, a sample recorded at the beginning of a monitoring period will be most affected by battery depletion than a sample recorded much later in the period.
  • Corrected voltage V for each discrete decoded data value can be determined based on the equation: V = D B S 2 b
    Figure imgb0001

    where D is the decoded value, B is the battery voltage as a function of the number of the sample S, and b is the number of bits in the input stream. The corrected voltage will typically fall in the range of 0-3.2VDC, while the battery voltage varies between 2.7-3.2VDC. The number of samples will depend on the capacity of the non-volatile memory. For example, a 32MB memory can store between 0-2* 225 samples. Other discharge profile adjustments could be utilized.
  • During ECG monitoring, feedback is introduced to avoid saturating the input amplifier 13b. A feedback marker is added to the data stream to indicate the change in feedback mode. During post-processing, the feedback can be removed to extend the effective dynamic range of the monitoring data. The data resolution, as expressed by number of bits n, can be determined based on the equation: n = ln a ln 2 + b
    Figure imgb0002

    where a is an amplification factor and b is the number of bits in the decoded input stream. The amplification factor can range up to around 750, depending upon the circuit layout and particularly on the op-amp used. In one embodiment, the effective number of bits doubles the resolution to 20-bits. Other data resolution values could be achieved.
  • The affects of feedback on the data stream are removed by subtracting the feedback's contribution ERLD, which can be determined based on the equation: E RLD = C 2 V O RLD e - t R RLD C 2
    Figure imgb0003

    where C is the parasitic capacitance of the patient, V O RLD
    Figure imgb0004
    is the last voltage output on the feedback circuit, RRLD is the output resistance value of the feedback circuit, and T is the time between samples. The energy contribution of the RLD can be converted into voltage, which can be determined based on the equation: V = C 2 E RLD
    Figure imgb0005

    where V is the voltage contribution of the feedback circuit, C is the self capacitance of the patient and ERLD is the energy contribution of the right leg drive. Other feedback cancellation methodologies could also be employed.
  • While the invention has been particularly shown and described as referenced to the embodiments thereof, those skilled in the art will understand that the foregoing and other changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims (15)

  1. A microcontrolled electrocardiographic monitoring circuit (10) with differential voltage encoding, comprising:
    an input signal path (23) comprising an electrode (12a), a low pass filter (13a), and an amplifier (13b), each connected in-line, the electrode (12a) sensing an input signal via a conductive surface and the amplifier (13b) outputting a filtered amplified output signal;
    a microcontroller circuit (11) comprising an input codec, comprising:
    an analog-to-digital converter (14) connected to the input signal path (23) through an output of the amplifier (13b) and converting the filtered amplified output signal into a data stream (31) of discrete digital values; and
    an encoder (33) determining a differential voltage between a current discrete digital value and a prior discrete digital value in the data stream (31); and
    persistent memory (17) connected to the microcontroller circuit (11) via a peripheral serial interface bus (18), wherein the differential voltages for each of the discrete digital values in the data stream (31) are stored into the persistent memory (17).
  2. A circuit according to Claim 1, wherein the encoder (33) further comprises selecting an encoded value representative of the differential voltage and the encoded value is stored into the persistent memory (17) instead of the differential voltage.
  3. A circuit according to Claim 2, wherein each of the encoded values is retrieved from 1 the persistent memory (17) and analog cardiac action potential signals are reproduced from the retrieved encoded values.
  4. A circuit according to Claim 1, further comprising:
    a set of enumerated ranges of voltage differences, wherein an encoded value is assigned to each of the enumerated ranges and the encoder (33) further comprises identifying the enumerated range within which the differential voltage falls and selecting the encoded value corresponding to the identified enumerated range.
  5. A circuit according to any preceding Claim, further comprising:
    a feedback generation module (32) comprised in the microcontroller circuit (11) and identifying a pairing of drive resistor settings matched to each discrete digital value in the data stream (31), which are output from the microcontroller circuit (11) as a digital feedback signal through a pair of output terminals; and
    an output signal path (24) comprising an electrode (12b) and a buffer (20), each connected in-line, and a pair of drive resistors connected in parallel to an input terminal of the buffer (20) and to the output terminals of the feedback module, each drive resistor being adjusted according to the digital feedback signal, and the electrode (12b) providing an output signal via a conductive surface.
  6. A circuit according to Claim 5, wherein the feedback module generates a feedback marker that is stored into the persistent memory (17) in sequence with the discrete digital values in the data stream (31).
  7. A circuit according to Claim 6, wherein each of the differential voltages is retrieved from the persistent memory (17) and analog cardiac action potential signals are reproduced from the retrieved differential voltages and a contribution from feedback is determined from the feedback marker and subtracted from the analog cardiac action potential signals.
  8. A circuit according to Claim 7, wherein resolution of each discrete digital value is extended as a function of the subtraction of feedback contribution before analog cardiac action potential signals reproduction.
  9. A circuit according to any preceding Claim, wherein each discrete data value comprises a voltage representative of an analog cardiac action potential signal and a voltage of a power supply comprised with the microcontroller circuit (11) is determined and the voltage for each of the discrete data values are normalized against depletion of the voltage of the power supply over a monitoring period.
  10. A circuit according to Claim 9, wherein the voltage of the power supply is scaled based on a number of write operations into the persistent memory (17) and the voltage for each of the discrete data values depends upon placement of the specific retrieved data value within an ordering of all of the retrieved data values.
  11. A microcontrolled electrocardiographic monitoring circuit (10) with discrete data encoding, comprising:
    an input signal path (23) comprising an electrode (12a), a low pass filter (13a), and an amplifier (13b), each connected in-line, the electrode (12a) sensing an input signal via a conductive surface and the amplifier (13b) outputting a filtered amplified output signal;
    a microcontroller circuit (11) comprising an input codec, comprising:
    an analog-to-digital converter (14) connected to the input signal path (23) through an output of the amplifier (13b) and converting the filtered amplified output signal into a data stream (31) of discrete digital values;
    an encoder (33) determining a differential voltage between a current discrete digital value and a prior discrete digital value in the data stream (31) and selecting an encoded value representative of the differential voltage; and
    persistent memory (17) connected to the microcontroller circuit (11) via a peripheral serial interface bus (18), wherein the encoded values for each of the differential voltages are stored into the persistent memory (17).
  12. A circuit according to Claim 11, further comprising:
    a set of enumerated ranges of voltage differences that each correspond to lower and upper bounds of voltage, wherein an encoded value is assigned to each of the enumerated ranges and the encoder (33) further comprises identifying the enumerated range within which the differential voltage falls by comparing the differential voltage to the lower and upper bounds of voltage.
  13. A circuit according to Claim 11 or claim 12, wherein each of the encoded values is retrieved from the persistent memory (17) and analog cardiac action potential signals are reproduced from the retrieved encoded values.
  14. A circuit according to any one of Claims 11 to 13, wherein each discrete data value comprises a voltage representative of an analog cardiac action potential signal, further comprising:
    a power supply comprised with the microcontroller circuit (11); and
    a reference compensation module determining a voltage for the power supply and normalizing each of the discrete data values against depletion of the voltage of the power supply over a monitoring period.
  15. A circuit according to Claim 14, wherein the voltage of the power supply is scaled based on a number of write operations into the persistent memory (17) and the voltage for each of the discrete data values depends upon placement of the specific retrieved data value within an ordering of all of the retrieved data values.
EP11184341A 2010-10-08 2011-10-07 Microcontrolled electrocardiographic monitoring circuit with differential voltage encoding Withdrawn EP2438851A3 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US12/901,460 US8239012B2 (en) 2010-10-08 2010-10-08 Microcontrolled electrocardiographic monitoring circuit with differential voltage encoding

Publications (2)

Publication Number Publication Date
EP2438851A2 true EP2438851A2 (en) 2012-04-11
EP2438851A3 EP2438851A3 (en) 2012-07-11

Family

ID=44903084

Family Applications (1)

Application Number Title Priority Date Filing Date
EP11184341A Withdrawn EP2438851A3 (en) 2010-10-08 2011-10-07 Microcontrolled electrocardiographic monitoring circuit with differential voltage encoding

Country Status (2)

Country Link
US (3) US8239012B2 (en)
EP (1) EP2438851A3 (en)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105320635A (en) * 2015-09-14 2016-02-10 陈钦碧 Method for realizing MAX 2769 interface control by adopting universal digital I/O
EP2903509A4 (en) * 2012-10-07 2016-06-01 Rhythm Diagnostics Systems Inc Wearable cardiac monitor
US9408551B2 (en) 2013-11-14 2016-08-09 Bardy Diagnostics, Inc. System and method for facilitating diagnosis of cardiac rhythm disorders with the aid of a digital computer
US9408545B2 (en) 2013-09-25 2016-08-09 Bardy Diagnostics, Inc. Method for efficiently encoding and compressing ECG data optimized for use in an ambulatory ECG monitor
WO2016126931A1 (en) * 2015-02-04 2016-08-11 Bardy Diagnostics, Inc. Efficiently encoding and compressing ecg data optimized for use in an ambulatory ecg monitor
US9433380B1 (en) 2013-09-25 2016-09-06 Bardy Diagnostics, Inc. Extended wear electrocardiography patch
US9433367B2 (en) 2013-09-25 2016-09-06 Bardy Diagnostics, Inc. Remote interfacing of extended wear electrocardiography and physiological sensor monitor
WO2016145314A1 (en) * 2015-03-11 2016-09-15 Medicomp, Inc. Wireless ecg sensor system and method
US9504423B1 (en) 2015-10-05 2016-11-29 Bardy Diagnostics, Inc. Method for addressing medical conditions through a wearable health monitor with the aid of a digital computer
US9545204B2 (en) 2013-09-25 2017-01-17 Bardy Diagnostics, Inc. Extended wear electrocardiography patch
US9545228B2 (en) 2013-09-25 2017-01-17 Bardy Diagnostics, Inc. Extended wear electrocardiography and respiration-monitoring patch
US9554715B2 (en) 2013-09-25 2017-01-31 Bardy Diagnostics, Inc. System and method for electrocardiographic data signal gain determination with the aid of a digital computer
US9619660B1 (en) 2013-09-25 2017-04-11 Bardy Diagnostics, Inc. Computer-implemented system for secure physiological data collection and processing
US9615763B2 (en) 2013-09-25 2017-04-11 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitor recorder optimized for capturing low amplitude cardiac action potential propagation
US9655537B2 (en) 2013-09-25 2017-05-23 Bardy Diagnostics, Inc. Wearable electrocardiography and physiology monitoring ensemble
US9655538B2 (en) 2013-09-25 2017-05-23 Bardy Diagnostics, Inc. Self-authenticating electrocardiography monitoring circuit
US9700227B2 (en) 2013-09-25 2017-07-11 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitoring patch optimized for capturing low amplitude cardiac action potential propagation
US9717432B2 (en) 2013-09-25 2017-08-01 Bardy Diagnostics, Inc. Extended wear electrocardiography patch using interlaced wire electrodes
US9717433B2 (en) 2013-09-25 2017-08-01 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitoring patch optimized for capturing low amplitude cardiac action potential propagation
US9737224B2 (en) 2013-09-25 2017-08-22 Bardy Diagnostics, Inc. Event alerting through actigraphy embedded within electrocardiographic data
US9775536B2 (en) 2013-09-25 2017-10-03 Bardy Diagnostics, Inc. Method for constructing a stress-pliant physiological electrode assembly
US10165946B2 (en) 2013-09-25 2019-01-01 Bardy Diagnostics, Inc. Computer-implemented system and method for providing a personal mobile device-triggered medical intervention
US10244949B2 (en) 2012-10-07 2019-04-02 Rhythm Diagnostic Systems, Inc. Health monitoring systems and methods
US10251576B2 (en) 2013-09-25 2019-04-09 Bardy Diagnostics, Inc. System and method for ECG data classification for use in facilitating diagnosis of cardiac rhythm disorders with the aid of a digital computer
USD850626S1 (en) 2013-03-15 2019-06-04 Rhythm Diagnostic Systems, Inc. Health monitoring apparatuses

Families Citing this family (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011146708A2 (en) 2010-05-21 2011-11-24 Medicomp, Inc. Retractable multi-use cardiac monitor
US9585584B2 (en) 2010-05-21 2017-03-07 Medicomp, Inc. Physiological signal monitor with retractable wires
US9037477B2 (en) 2010-10-08 2015-05-19 Cardiac Science Corporation Computer-implemented system and method for evaluating ambulatory electrocardiographic monitoring of cardiac rhythm disorders
US8613708B2 (en) 2010-10-08 2013-12-24 Cardiac Science Corporation Ambulatory electrocardiographic monitor with jumpered sensing electrode
US20120089000A1 (en) 2010-10-08 2012-04-12 Jon Mikalson Bishay Ambulatory Electrocardiographic Monitor For Providing Ease Of Use In Women And Method Of Use
US8239012B2 (en) 2010-10-08 2012-08-07 Cardiac Science Corporation Microcontrolled electrocardiographic monitoring circuit with differential voltage encoding
US8880352B2 (en) * 2010-11-29 2014-11-04 Siemens Aktiengesellschaft System and method for analyzing an electrophysiological signal
CA2905091A1 (en) * 2013-03-15 2014-09-25 Altria Client Services Llc System and method of obtaining smoking topography data
US9793717B2 (en) 2013-08-23 2017-10-17 Qualcomm Incorporated Apparatus and method for non-compliant object detection
WO2016044477A1 (en) * 2014-09-16 2016-03-24 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitor recorder
USD744659S1 (en) 2013-11-07 2015-12-01 Bardy Diagnostics, Inc. Extended wear electrode patch
USD801528S1 (en) 2013-11-07 2017-10-31 Bardy Diagnostics, Inc. Electrocardiography monitor
USD717955S1 (en) 2013-11-07 2014-11-18 Bardy Diagnostics, Inc. Electrocardiography monitor
USD831833S1 (en) 2013-11-07 2018-10-23 Bardy Diagnostics, Inc. Extended wear electrode patch
CN103638600B (en) * 2013-12-25 2015-08-19 哈尔滨工业大学 Intelligent multi-channel electrical stimulation SEMG feedback system
USD766447S1 (en) 2015-09-10 2016-09-13 Bardy Diagnostics, Inc. Extended wear electrode patch
USD793566S1 (en) 2015-09-10 2017-08-01 Bardy Diagnostics, Inc. Extended wear electrode patch

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5392784A (en) 1993-08-20 1995-02-28 Hewlett-Packard Company Virtual right leg drive and augmented right leg drive circuits for common mode voltage reduction in ECG and EEG measurements
US20070225611A1 (en) 2006-02-06 2007-09-27 Kumar Uday N Non-invasive cardiac monitor and methods of using continuously recorded cardiac data
US20080284599A1 (en) 2005-04-28 2008-11-20 Proteus Biomedical, Inc. Pharma-Informatics System
US20080306359A1 (en) 2005-09-01 2008-12-11 Zdeblick Mark J Medical Diagnostic and Treatment Platform Using Near-Field Wireless Communication of Information Within a Patient's Body

Family Cites Families (118)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3215136A (en) 1962-07-06 1965-11-02 Holter Res Foundation Inc Electrocardiographic means
US4073011A (en) 1976-08-25 1978-02-07 Del Mar Avionics Electrocardiographic computer
US4532934A (en) 1978-11-01 1985-08-06 Del Mar Avionics Pacemaker monitoring recorder and malfunction analyzer
US4550502A (en) 1983-04-15 1985-11-05 Joseph Grayzel Device for analysis of recorded electrocardiogram
FR2571603B1 (en) 1984-10-11 1989-01-06 Ascher Gilles Portable Recorder electrocardiograms
US4716903A (en) * 1986-10-06 1988-01-05 Telectronics N.V. Storage in a pacemaker memory
US4915656A (en) 1988-10-21 1990-04-10 Physio-Control Corporation Discriminating medical electrode connector
US5199432A (en) 1990-10-30 1993-04-06 American Home Products Corporation Fetal electrode product for use in monitoring fetal heart rate
US6605046B1 (en) 1991-06-03 2003-08-12 Del Mar Medical Systems, Llc Ambulatory physio-kinetic monitor with envelope enclosure
US5215098A (en) * 1991-08-12 1993-06-01 Telectronics Pacing Systems, Inc. Data compression of cardiac electrical signals using scanning correlation and temporal data compression
US5984102A (en) 1992-09-24 1999-11-16 Survivalink Corporation Medical electrode packaging technology
US5402884A (en) 1992-09-24 1995-04-04 Surviva Link Corporation Medical electrode packaging technology
US5473537A (en) 1993-07-30 1995-12-05 Psychresources Development Company Method for evaluating and reviewing a patient's condition
US5458141A (en) 1993-08-04 1995-10-17 Quinton Instrument Company Abrasive skin electrode
USD357069S (en) 1993-08-25 1995-04-04 Quinton Instrument Company Medical electrode
US5402780A (en) 1993-09-02 1995-04-04 Faasse, Jr.; Adrian L. Medical electrode with offset contact stud
DE4329898A1 (en) 1993-09-04 1995-04-06 Marcus Dr Besson Wireless medical diagnostic and monitoring equipment
FR2722313B1 (en) * 1994-07-07 1997-04-25 Ela Medical Sa Process for the compression of physiological data, in particular cardiac active, in particular for a recording holter Electrocardiogram or electrogram
DE69421530D1 (en) 1994-09-10 1999-12-09 Hewlett Packard Gmbh Apparatus and method for potential equalization of a patient with regard to medical instruments
US5697955A (en) 1996-05-10 1997-12-16 Survivalink Corporation Defibrillator electrodes and date code detector circuit
US5749902A (en) 1996-05-22 1998-05-12 Survivalink Corporation Recorded data correction method and apparatus for isolated clock systems
US6101413A (en) 1996-06-04 2000-08-08 Survivalink Corporation Circuit detectable pediatric defibrillation electrodes
US5817151A (en) 1996-06-04 1998-10-06 Survivalink Corporation Circuit detectable packaged medical electrodes
US5951598A (en) 1997-01-14 1999-09-14 Heartstream, Inc. Electrode system
US6148233A (en) 1997-03-07 2000-11-14 Cardiac Science, Inc. Defibrillation system having segmented electrodes
US7756721B1 (en) 1997-03-14 2010-07-13 Best Doctors, Inc. Health care management system
US5906583A (en) 1997-08-20 1999-05-25 R.Z. Comparative Diagnostics Ltd. Automatic cardiometer
US6115638A (en) 1998-05-04 2000-09-05 Survivalink Corporation Medical electrode with conductive release liner
WO1999059673A1 (en) 1998-05-21 1999-11-25 Medtronic Physio-Control Manufacturing Corp. Automatic detection and reporting of cardiac asystole
US6134479A (en) 1998-07-09 2000-10-17 Survivalink Corporation Electrode triad for external defibrillation
US6272385B1 (en) 1998-09-01 2001-08-07 Agilent Technologies, Inc. Independently deployable sealed defibrillator electrode pad and method of use
US6108578A (en) 1998-09-02 2000-08-22 Heartstream, Inc. Configurable arrhythmia analysis algorithm
US6117077A (en) 1999-01-22 2000-09-12 Del Mar Medical Systems, Llc Long-term, ambulatory physiological recorder
US7429243B2 (en) 1999-06-03 2008-09-30 Cardiac Intelligence Corporation System and method for transacting an automated patient communications session
CA2314513A1 (en) 1999-07-26 2001-01-26 Gust H. Bardy System and method for providing normalized voice feedback from an individual patient in an automated collection and analysis patient care system
US6607485B2 (en) 1999-06-03 2003-08-19 Cardiac Intelligence Corporation Computer readable storage medium containing code for automated collection and analysis of patient information retrieved from an implantable medical device for remote patient care
US6312378B1 (en) 1999-06-03 2001-11-06 Cardiac Intelligence Corporation System and method for automated collection and analysis of patient information retrieved from an implantable medical device for remote patient care
US7134996B2 (en) 1999-06-03 2006-11-14 Cardiac Intelligence Corporation System and method for collection and analysis of patient information for automated remote patient care
US6270457B1 (en) 1999-06-03 2001-08-07 Cardiac Intelligence Corp. System and method for automated collection and analysis of regularly retrieved patient information for remote patient care
FR2795300B1 (en) 1999-06-23 2002-01-04 Ela Medical Sa Holter type apparatus for recording physiological signals of cardiac activity
CA2314517A1 (en) 1999-07-26 2001-01-26 Gust H. Bardy System and method for determining a reference baseline of individual patient status for use in an automated collection and analysis patient care system
US6221011B1 (en) 1999-07-26 2001-04-24 Cardiac Intelligence Corporation System and method for determining a reference baseline of individual patient status for use in an automated collection and analysis patient care system
US6304783B1 (en) 1999-10-14 2001-10-16 Heartstream, Inc. Defibrillator system including a removable monitoring electrodes adapter and method of detecting the monitoring adapter
US6368284B1 (en) 1999-11-16 2002-04-09 Cardiac Intelligence Corporation Automated collection and analysis patient care system and method for diagnosing and monitoring myocardial ischemia and outcomes thereof
US8369937B2 (en) 1999-11-16 2013-02-05 Cardiac Pacemakers, Inc. System and method for prioritizing medical conditions
US6398728B1 (en) 1999-11-16 2002-06-04 Cardiac Intelligence Corporation Automated collection and analysis patient care system and method for diagnosing and monitoring respiratory insufficiency and outcomes thereof
US6411840B1 (en) 1999-11-16 2002-06-25 Cardiac Intelligence Corporation Automated collection and analysis patient care system and method for diagnosing and monitoring the outcomes of atrial fibrillation
US6336903B1 (en) 1999-11-16 2002-01-08 Cardiac Intelligence Corp. Automated collection and analysis patient care system and method for diagnosing and monitoring congestive heart failure and outcomes thereof
US7085601B1 (en) 1999-11-17 2006-08-01 Koninklijke Philips Electronics N.V. External atrial defibrillator and method for personal termination of atrial fibrillation
DE19955211A1 (en) 1999-11-17 2001-05-31 Siemens Ag Patient referral method for referring patient to other medical department
US6912424B2 (en) 1999-12-01 2005-06-28 Meagan, Medical, Inc. Apparatus and method for coupling therapeutic and/or monitoring equipment to a patient
US20020026223A1 (en) 1999-12-24 2002-02-28 Riff Kenneth M. Method and a system for using implanted medical device data for accessing therapies
US6496721B1 (en) 2000-04-28 2002-12-17 Cardiac Pacemakers, Inc. Automatic input impedance balancing for electrocardiogram (ECG) sensing applications
US20040049132A1 (en) 2000-06-15 2004-03-11 The Procter & Gamble Company Device for body activity detection and processing
CA2420236A1 (en) 2000-08-22 2002-02-28 Medtronic, Inc. Medical device systems implemented network system for remote patient management
US6665559B2 (en) 2000-10-06 2003-12-16 Ge Medical Systems Information Technologies, Inc. Method and apparatus for perioperative assessment of cardiovascular risk
US6754523B2 (en) 2000-11-28 2004-06-22 J. Gerald Toole Method of analysis of the electrocardiogram
US7412395B2 (en) 2000-12-29 2008-08-12 Ge Medical Systems Information Technologies, Inc. Automated scheduling of emergency procedure based on identification of high-risk patient
US6719689B2 (en) * 2001-04-30 2004-04-13 Medtronic, Inc. Method and system for compressing and storing data in a medical device having limited storage
US6671547B2 (en) 2001-06-13 2003-12-30 Koninklijke Philips Electronics N.V. Adaptive analysis method for an electrotherapy device and apparatus
US6782293B2 (en) 2001-09-14 2004-08-24 Zoll Medical Corporation Defibrillation electrode assembly including CPR pad
AUPR823701A0 (en) 2001-10-12 2001-11-08 Studico Pty Ltd Service provider selection and management system
US20030083559A1 (en) 2001-10-31 2003-05-01 Thompson David L. Non-contact monitor
US6993377B2 (en) 2002-02-22 2006-01-31 The Board Of Trustees Of The University Of Arkansas Method for diagnosing heart disease, predicting sudden death, and analyzing treatment response using multifractal analysis
US6978169B1 (en) 2002-04-04 2005-12-20 Guerra Jim J Personal physiograph
US20040034284A1 (en) 2002-04-10 2004-02-19 Aversano Thomas R. Patient initiated emergency response system
US7027864B2 (en) 2002-04-17 2006-04-11 Koninklijke Philips Electronics N.V. Defibrillation system and method designed for rapid attachment
US7065401B2 (en) 2002-05-08 2006-06-20 Michael Worden Method of applying electrical signals to a patient and automatic wearable external defibrillator
US20040008123A1 (en) 2002-07-15 2004-01-15 Battelle Memorial Institute System and method for tracking medical devices
US7257438B2 (en) 2002-07-23 2007-08-14 Datascope Investment Corp. Patient-worn medical monitoring device
CA2560323C (en) 2004-03-22 2014-01-07 Bodymedia, Inc. Non-invasive temperature monitoring device
US20040087836A1 (en) 2002-10-31 2004-05-06 Green Michael R. Computer system and method for closed-loop support of patient self-testing
US8332233B2 (en) 2002-11-13 2012-12-11 Biomedical Systems Corporation Method and system for collecting and analyzing holter data employing a web site
US7248688B2 (en) 2003-01-27 2007-07-24 Bellsouth Intellectual Property Corporation Virtual physician office systems and methods
US20040243435A1 (en) 2003-05-29 2004-12-02 Med-Sched, Inc. Medical information management system
US20040260188A1 (en) 2003-06-17 2004-12-23 The General Hospital Corporation Automated auscultation system
US7267278B2 (en) 2003-06-23 2007-09-11 Robert Lammle Method and system for providing pharmaceutical product information to a patient
US20050020889A1 (en) 2003-07-24 2005-01-27 Garboski Dennis P. Medical monitoring system
WO2005112749A1 (en) 2004-05-12 2005-12-01 Zoll Medical Corporation Ecg rhythm advisory method
US7565194B2 (en) 2004-05-12 2009-07-21 Zoll Medical Corporation ECG rhythm advisory method
US20070050209A1 (en) 2004-11-08 2007-03-01 Paul Yered Method for Providing Prescriptions and Additional Services at Lower Costs Using an Ethnic and Demographic Prescription Program
US7343198B2 (en) 2004-08-23 2008-03-11 The University Of Texas At Arlington System, software, and method for detection of sleep-disordered breathing using an electrocardiogram
US20060122469A1 (en) 2004-11-16 2006-06-08 Martel Normand M Remote medical monitoring system
JP2008536545A (en) 2005-03-21 2008-09-11 ヘルス−スマート リミテッド System for continuous blood pressure monitoring
US20060224072A1 (en) 2005-03-31 2006-10-05 Cardiovu, Inc. Disposable extended wear heart monitor patch
US20070003115A1 (en) 2005-06-30 2007-01-04 Eastman Kodak Company Remote diagnostic device for medical testing
US20070078324A1 (en) 2005-09-30 2007-04-05 Textronics, Inc. Physiological Monitoring Wearable Having Three Electrodes
US20070093719A1 (en) 2005-10-20 2007-04-26 Nichols Allen B Jr Personal heart rhythm recording device
US20070123801A1 (en) 2005-11-28 2007-05-31 Daniel Goldberger Wearable, programmable automated blood testing system
EP1956973B1 (en) 2005-11-30 2017-09-13 Koninklijke Philips N.V. Electro-mechanical connector for thin medical monitoring patch
US20070136091A1 (en) 2005-12-13 2007-06-14 Mctaggart Ryan Method and system for patient transfers and referrals
USD558882S1 (en) 2006-03-14 2008-01-01 Unomedical Limited Biomedical electrode for attachment to skin
US7702382B2 (en) 2006-04-17 2010-04-20 General Electric Company Multi-tier system for cardiology and patient monitoring data analysis
US7558622B2 (en) 2006-05-24 2009-07-07 Bao Tran Mesh network stroke monitoring appliance
GB0610292D0 (en) 2006-05-24 2006-07-05 Melys Diagnostics Ltd Heart monitor
US8075500B2 (en) 2007-07-17 2011-12-13 Biopad Ltd. Fetal wellbeing monitoring apparatus and pad therefor
WO2008010216A2 (en) 2006-07-18 2008-01-24 Biopad Ltd Fetal motor activity monitoring apparatus and pad therfor
US8073740B1 (en) 2006-08-15 2011-12-06 Amazon Technologies, Inc. Facilitating a supply of used items
US8214007B2 (en) 2006-11-01 2012-07-03 Welch Allyn, Inc. Body worn physiological sensor device having a disposable electrode module
US8315687B2 (en) 2006-12-07 2012-11-20 Koninklijke Philips Electronics N.V. Handheld, repositionable ECG detector
US7787943B2 (en) 2007-07-25 2010-08-31 Mcdonough Daniel K Heart rate monitor for swimmers
WO2009112979A1 (en) 2008-03-10 2009-09-17 Koninklijke Philips Electronics N.V. Cellphone handset with a custom control program for an egg monitoring system
RU2010141557A (en) 2008-03-10 2012-04-20 Конинклейке Филипс Электроникс Н.В. (Nl) Cell Phone Handset with lid for ECG monitoring system
CN101971196A (en) 2008-03-10 2011-02-09 皇家飞利浦电子股份有限公司 A method for refurbishing ecg monitoring systems
CN101984743B (en) 2008-03-10 2013-06-19 皇家飞利浦电子股份有限公司 Continuous outpatient ECG monitoring system
US7881785B2 (en) 2008-03-26 2011-02-01 Cardiac Science Corporation Method and apparatus for defrosting a defibrillation electrode
USD606656S1 (en) 2008-04-04 2009-12-22 Seiko Epson Corporation Wrist watch type purse sensor
US7996070B2 (en) 2008-04-24 2011-08-09 Medtronic, Inc. Template matching method for monitoring of ECG morphology changes
US20090292194A1 (en) 2008-05-23 2009-11-26 Corventis, Inc. Chiropractic Care Management Systems and Methods
DE102008054442A1 (en) 2008-12-10 2010-06-17 Robert Bosch Gmbh Method for remote diagnostic monitoring and support of patients and the establishment and telemedical center
USD639437S1 (en) 2010-10-08 2011-06-07 Cardiac Science Corporation Wearable ambulatory electrocardiographic monitor
US20120089000A1 (en) 2010-10-08 2012-04-12 Jon Mikalson Bishay Ambulatory Electrocardiographic Monitor For Providing Ease Of Use In Women And Method Of Use
US9037477B2 (en) 2010-10-08 2015-05-19 Cardiac Science Corporation Computer-implemented system and method for evaluating ambulatory electrocardiographic monitoring of cardiac rhythm disorders
US20120089001A1 (en) 2010-10-08 2012-04-12 Jon Mikalson Bishay Ambulatory Electrocardiographic Monitor And Method Of Use
US8285370B2 (en) 2010-10-08 2012-10-09 Cardiac Science Corporation Microcontrolled electrocardiographic monitoring circuit with feedback control
US20120089417A1 (en) 2010-10-08 2012-04-12 Bardy Gust H Computer-Implemented System And Method For Mediating Patient-Initiated Physiological Monitoring
US8239012B2 (en) 2010-10-08 2012-08-07 Cardiac Science Corporation Microcontrolled electrocardiographic monitoring circuit with differential voltage encoding
US8613708B2 (en) 2010-10-08 2013-12-24 Cardiac Science Corporation Ambulatory electrocardiographic monitor with jumpered sensing electrode

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5392784A (en) 1993-08-20 1995-02-28 Hewlett-Packard Company Virtual right leg drive and augmented right leg drive circuits for common mode voltage reduction in ECG and EEG measurements
US20080284599A1 (en) 2005-04-28 2008-11-20 Proteus Biomedical, Inc. Pharma-Informatics System
US20080306359A1 (en) 2005-09-01 2008-12-11 Zdeblick Mark J Medical Diagnostic and Treatment Platform Using Near-Field Wireless Communication of Information Within a Patient's Body
US20070225611A1 (en) 2006-02-06 2007-09-27 Kumar Uday N Non-invasive cardiac monitor and methods of using continuously recorded cardiac data
US20070249946A1 (en) 2006-02-06 2007-10-25 Kumar Uday N Non-invasive cardiac monitor and methods of using continuously recorded cardiac data
US20070255153A1 (en) 2006-02-06 2007-11-01 Kumar Uday N Non-invasive cardiac monitor and methods of using continuously recorded cardiac data

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
P. LIBBY ET AL.: "Braunwald's Heart Disease - A Textbook of Cardiovascular Medicine(8th ed.)", 2008

Cited By (53)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9782132B2 (en) 2012-10-07 2017-10-10 Rhythm Diagnostic Systems, Inc. Health monitoring systems and methods
EP2903509A4 (en) * 2012-10-07 2016-06-01 Rhythm Diagnostics Systems Inc Wearable cardiac monitor
US10244949B2 (en) 2012-10-07 2019-04-02 Rhythm Diagnostic Systems, Inc. Health monitoring systems and methods
US10080527B2 (en) 2012-10-07 2018-09-25 Rhythm Diagnostic Systems, Inc. Health monitoring systems and methods
USD850626S1 (en) 2013-03-15 2019-06-04 Rhythm Diagnostic Systems, Inc. Health monitoring apparatuses
US9619660B1 (en) 2013-09-25 2017-04-11 Bardy Diagnostics, Inc. Computer-implemented system for secure physiological data collection and processing
US9433367B2 (en) 2013-09-25 2016-09-06 Bardy Diagnostics, Inc. Remote interfacing of extended wear electrocardiography and physiological sensor monitor
US10271756B2 (en) 2013-09-25 2019-04-30 Bardy Diagnostics, Inc. Monitor recorder optimized for electrocardiographic signal processing
US10271755B2 (en) 2013-09-25 2019-04-30 Bardy Diagnostics, Inc. Method for constructing physiological electrode assembly with sewn wire interconnects
US9545204B2 (en) 2013-09-25 2017-01-17 Bardy Diagnostics, Inc. Extended wear electrocardiography patch
US9545228B2 (en) 2013-09-25 2017-01-17 Bardy Diagnostics, Inc. Extended wear electrocardiography and respiration-monitoring patch
US9554715B2 (en) 2013-09-25 2017-01-31 Bardy Diagnostics, Inc. System and method for electrocardiographic data signal gain determination with the aid of a digital computer
US10265015B2 (en) 2013-09-25 2019-04-23 Bardy Diagnostics, Inc. Monitor recorder optimized for electrocardiography and respiratory data acquisition and processing
US9615763B2 (en) 2013-09-25 2017-04-11 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitor recorder optimized for capturing low amplitude cardiac action potential propagation
US9642537B2 (en) 2013-09-25 2017-05-09 Bardy Diagnostics, Inc. Ambulatory extended-wear electrocardiography and syncope sensor monitor
US9655537B2 (en) 2013-09-25 2017-05-23 Bardy Diagnostics, Inc. Wearable electrocardiography and physiology monitoring ensemble
US9655538B2 (en) 2013-09-25 2017-05-23 Bardy Diagnostics, Inc. Self-authenticating electrocardiography monitoring circuit
US9700227B2 (en) 2013-09-25 2017-07-11 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitoring patch optimized for capturing low amplitude cardiac action potential propagation
US9717432B2 (en) 2013-09-25 2017-08-01 Bardy Diagnostics, Inc. Extended wear electrocardiography patch using interlaced wire electrodes
US9717433B2 (en) 2013-09-25 2017-08-01 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitoring patch optimized for capturing low amplitude cardiac action potential propagation
US9730641B2 (en) 2013-09-25 2017-08-15 Bardy Diagnostics, Inc. Monitor recorder-implemented method for electrocardiography value encoding and compression
US9730593B2 (en) 2013-09-25 2017-08-15 Bardy Diagnostics, Inc. Extended wear ambulatory electrocardiography and physiological sensor monitor
US9737211B2 (en) 2013-09-25 2017-08-22 Bardy Diagnostics, Inc. Ambulatory rescalable encoding monitor recorder
US9737224B2 (en) 2013-09-25 2017-08-22 Bardy Diagnostics, Inc. Event alerting through actigraphy embedded within electrocardiographic data
US9775536B2 (en) 2013-09-25 2017-10-03 Bardy Diagnostics, Inc. Method for constructing a stress-pliant physiological electrode assembly
US9433380B1 (en) 2013-09-25 2016-09-06 Bardy Diagnostics, Inc. Extended wear electrocardiography patch
US10165946B2 (en) 2013-09-25 2019-01-01 Bardy Diagnostics, Inc. Computer-implemented system and method for providing a personal mobile device-triggered medical intervention
US9820665B2 (en) 2013-09-25 2017-11-21 Bardy Diagnostics, Inc. Remote interfacing of extended wear electrocardiography and physiological sensor monitor
US9901274B2 (en) 2013-09-25 2018-02-27 Bardy Diagnostics, Inc. Electrocardiography patch
US10278603B2 (en) 2013-09-25 2019-05-07 Bardy Diagnostics, Inc. System and method for secure physiological data acquisition and storage
US9955911B2 (en) 2013-09-25 2018-05-01 Bardy Diagnostics, Inc. Electrocardiography and respiratory monitor recorder
US9955888B2 (en) 2013-09-25 2018-05-01 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitor recorder optimized for internal signal processing
US10251576B2 (en) 2013-09-25 2019-04-09 Bardy Diagnostics, Inc. System and method for ECG data classification for use in facilitating diagnosis of cardiac rhythm disorders with the aid of a digital computer
US10004415B2 (en) 2013-09-25 2018-06-26 Bardy Diagnostics, Inc. Extended wear electrocardiography patch
US10045709B2 (en) 2013-09-25 2018-08-14 Bardy Diagnostics, Inc. System and method for facilitating a cardiac rhythm disorder diagnosis with the aid of a digital computer
US10052022B2 (en) 2013-09-25 2018-08-21 Bardy Diagnostics, Inc. System and method for providing dynamic gain over non-noise electrocardiographic data with the aid of a digital computer
US9408545B2 (en) 2013-09-25 2016-08-09 Bardy Diagnostics, Inc. Method for efficiently encoding and compressing ECG data optimized for use in an ambulatory ECG monitor
US10251575B2 (en) 2013-09-25 2019-04-09 Bardy Diagnostics, Inc. Wearable electrocardiography and physiology monitoring ensemble
US10111601B2 (en) 2013-09-25 2018-10-30 Bardy Diagnostics, Inc. Extended wear electrocardiography monitor optimized for capturing low amplitude cardiac action potential propagation
US10278606B2 (en) 2013-09-25 2019-05-07 Bardy Diagnostics, Inc. Ambulatory electrocardiography monitor optimized for capturing low amplitude cardiac action potential propagation
US10154793B2 (en) 2013-09-25 2018-12-18 Bardy Diagnostics, Inc. Extended wear electrocardiography patch with wire contact surfaces
US9955885B2 (en) 2013-09-25 2018-05-01 Bardy Diagnostics, Inc. System and method for physiological data processing and delivery
US10172534B2 (en) 2013-09-25 2019-01-08 Bardy Diagnostics, Inc. Remote interfacing electrocardiography patch
US10264992B2 (en) 2013-09-25 2019-04-23 Bardy Diagnostics, Inc. Extended wear sewn electrode electrocardiography monitor
US9408551B2 (en) 2013-11-14 2016-08-09 Bardy Diagnostics, Inc. System and method for facilitating diagnosis of cardiac rhythm disorders with the aid of a digital computer
WO2016126931A1 (en) * 2015-02-04 2016-08-11 Bardy Diagnostics, Inc. Efficiently encoding and compressing ecg data optimized for use in an ambulatory ecg monitor
WO2016145314A1 (en) * 2015-03-11 2016-09-15 Medicomp, Inc. Wireless ecg sensor system and method
US10098544B2 (en) 2015-03-11 2018-10-16 Medicomp, Inc. Wireless ECG sensor system and method
CN105320635A (en) * 2015-09-14 2016-02-10 陈钦碧 Method for realizing MAX 2769 interface control by adopting universal digital I/O
US9936875B2 (en) 2015-10-05 2018-04-10 Bardy Diagnostics, Inc. Health monitoring apparatus for initiating a treatment of a patient with the aid of a digital computer
US9504423B1 (en) 2015-10-05 2016-11-29 Bardy Diagnostics, Inc. Method for addressing medical conditions through a wearable health monitor with the aid of a digital computer
US9788722B2 (en) 2015-10-05 2017-10-17 Bardy Diagnostics, Inc. Method for addressing medical conditions through a wearable health monitor with the aid of a digital computer
US10123703B2 (en) 2015-10-05 2018-11-13 Bardy Diagnostics, Inc. Health monitoring apparatus with wireless capabilities for initiating a patient treatment with the aid of a digital computer

Also Published As

Publication number Publication date
US8239012B2 (en) 2012-08-07
US8938287B2 (en) 2015-01-20
EP2438851A3 (en) 2012-07-11
US20120302906A1 (en) 2012-11-29
US8626277B2 (en) 2014-01-07
US20140200472A1 (en) 2014-07-17
US20120089039A1 (en) 2012-04-12

Similar Documents

Publication Publication Date Title
Spach et al. Skin-electrode impedance and its effect on recording cardiac potentials
Duskalov et al. Developments in ECG acquisition, preprocessing, parameter measurement, and recording
EP1737343B1 (en) Collecting activity information to evaluate therapy
Neuman Biopotential amplifiers
CA2211844C (en) External patient reference sensor
Lim et al. ECG recording on a bed during sleep without direct skin-contact
US5309917A (en) System and method of impedance cardiography and heartbeat determination
EP1419731A1 (en) System and method for monitoring blood glucose levels using an implantable medical device
US20070073266A1 (en) Compact wireless biometric monitoring and real time processing system
US7305262B2 (en) Apparatus and method for acquiring oximetry and electrocardiogram signals
US20030045908A1 (en) Implantable medical device (IMD) system configurable to subject a patient to a stress test and to detect myocardial ischemia within the patient
US7603170B2 (en) Calibration of impedance monitoring of respiratory volumes using thoracic D.C. impedance
US7662104B2 (en) Method for correction of posture dependence on heart sounds
EP0472411A1 (en) Implantable ambulatory electrocardiogram monitor
US9808165B2 (en) Multi-function health monitor with integrated cellular module
Rautaharju et al. The exercise electrocardiogram: Experience in analysis of “noisy” cardiograms with a small computer
US8747314B2 (en) Cardiovascular pressure annotations and logbook
US20050222522A1 (en) Detecting sleep
US20070255152A1 (en) Apparatus and Method for Measuring Electric Non-Contact Electrocardiogram in Everyday Life
US6865419B2 (en) Method and apparatus for measurement of mean pulmonary artery pressure from a ventricle in an ambulatory monitor
US5025784A (en) Apparatus and method for detecting and processing impedance rheogram
EP1659936B1 (en) Apparatus and method for cordless recording and telecommunication transmission of three special ecg leads and their processing
JP4587008B2 (en) Standard 12-lead ECG construction method and electrocardiography devices
JP3816101B2 (en) Cardiac pacemaker
US20090048503A1 (en) Glycemic control monitoring using implantable medical device

Legal Events

Date Code Title Description
AX Request for extension of the european patent to

Countries concerned: BAME

AK Designated contracting states:

Kind code of ref document: A2

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AK Designated contracting states:

Kind code of ref document: A3

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

AX Request for extension of the european patent to

Countries concerned: BAME

RIC1 Classification (correction)

Ipc: A61B 5/0432 20060101ALI20120601BHEP

Ipc: A61B 5/0428 20060101ALI20120601BHEP

Ipc: A61B 5/0404 20060101AFI20120601BHEP

18D Deemed to be withdrawn

Effective date: 20130112